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* [PATCH v7 0/7] coroutines: generate wrapper code
@ 2020-06-10 10:03 Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 1/7] block: return error-code from bdrv_invalidate_cache Vladimir Sementsov-Ogievskiy
                   ` (7 more replies)
  0 siblings, 8 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

Hi all!

The aim of the series is to reduce code-duplication and writing
parameters structure-packing by hand around coroutine function wrappers.

Benefits:
 - no code duplication
 - less indirection

v7: apply Eric's suggestions
02: fix grammar in commit msg, add Eric's r-b
04: - don't create separate header for generated_co_wrapper thing
    - inline aio_wait_kick() call
    - use json.dumps to make style for clang-format
05: - drop "#include "block/generated-co-wrapper.h" (since the header is removed)
    - add Eric's r-b

Vladimir Sementsov-Ogievskiy (7):
  block: return error-code from bdrv_invalidate_cache
  block/io: refactor coroutine wrappers
  block: declare some coroutine functions in block/coroutines.h
  scripts: add coroutine-wrapper.py
  block: generate coroutine-wrapper code
  block: drop bdrv_prwv
  block/io: refactor save/load vmstate

 Makefile                     |   8 +
 block/block-gen.h            |  49 +++++
 block/coroutines.h           |  65 +++++++
 include/block/block.h        |  31 ++--
 block.c                      |  97 ++--------
 block/io.c                   | 336 +++++------------------------------
 tests/test-bdrv-drain.c      |   2 +-
 block/Makefile.objs          |   1 +
 scripts/coroutine-wrapper.py | 180 +++++++++++++++++++
 9 files changed, 388 insertions(+), 381 deletions(-)
 create mode 100644 block/block-gen.h
 create mode 100644 block/coroutines.h
 create mode 100755 scripts/coroutine-wrapper.py

-- 
2.21.0



^ permalink raw reply	[flat|nested] 13+ messages in thread
* [PATCH v7 1/7] block: return error-code from bdrv_invalidate_cache
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 2/7] block/io: refactor coroutine wrappers Vladimir Sementsov-Ogievskiy
                   ` (6 subsequent siblings)
  7 siblings, 0 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

This is the only coroutine wrapper from block.c and block/io.c which
doesn't return a value, so let's convert it to the common behavior, to
simplify moving to generated coroutine wrappers in a further commit.

Also, bdrv_invalidate_cache is a void function, returning error only
through **errp parameter, which is considered to be bad practice, as
it forces callers to define and propagate local_err variable, so
conversion is good anyway.

This patch leaves the conversion of .bdrv_co_invalidate_cache() driver
callbacks and bdrv_invalidate_cache_all() for another day.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 include/block/block.h |  2 +-
 block.c               | 32 ++++++++++++++++++--------------
 2 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/include/block/block.h b/include/block/block.h
index 25e299605e..46965a7780 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -464,7 +464,7 @@ void bdrv_aio_cancel_async(BlockAIOCB *acb);
 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
 
 /* Invalidate any cached metadata used by image formats */
-void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
+int bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
 void bdrv_invalidate_cache_all(Error **errp);
 int bdrv_inactivate_all(void);
 
diff --git a/block.c b/block.c
index 8416376c9b..b01551f21c 100644
--- a/block.c
+++ b/block.c
@@ -5643,8 +5643,8 @@ void bdrv_init_with_whitelist(void)
     bdrv_init();
 }
 
-static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
-                                                  Error **errp)
+static int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
+                                                 Error **errp)
 {
     BdrvChild *child, *parent;
     uint64_t perm, shared_perm;
@@ -5653,14 +5653,14 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
     BdrvDirtyBitmap *bm;
 
     if (!bs->drv)  {
-        return;
+        return -ENOMEDIUM;
     }
 
     QLIST_FOREACH(child, &bs->children, next) {
         bdrv_co_invalidate_cache(child->bs, &local_err);
         if (local_err) {
             error_propagate(errp, local_err);
-            return;
+            return -EINVAL;
         }
     }
 
@@ -5684,7 +5684,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
         if (ret < 0) {
             bs->open_flags |= BDRV_O_INACTIVE;
             error_propagate(errp, local_err);
-            return;
+            return ret;
         }
         bdrv_set_perm(bs, perm, shared_perm);
 
@@ -5693,7 +5693,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
             if (local_err) {
                 bs->open_flags |= BDRV_O_INACTIVE;
                 error_propagate(errp, local_err);
-                return;
+                return -EINVAL;
             }
         }
 
@@ -5705,7 +5705,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
         if (ret < 0) {
             bs->open_flags |= BDRV_O_INACTIVE;
             error_setg_errno(errp, -ret, "Could not refresh total sector count");
-            return;
+            return ret;
         }
     }
 
@@ -5715,27 +5715,30 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
             if (local_err) {
                 bs->open_flags |= BDRV_O_INACTIVE;
                 error_propagate(errp, local_err);
-                return;
+                return -EINVAL;
             }
         }
     }
+
+    return 0;
 }
 
 typedef struct InvalidateCacheCo {
     BlockDriverState *bs;
     Error **errp;
     bool done;
+    int ret;
 } InvalidateCacheCo;
 
 static void coroutine_fn bdrv_invalidate_cache_co_entry(void *opaque)
 {
     InvalidateCacheCo *ico = opaque;
-    bdrv_co_invalidate_cache(ico->bs, ico->errp);
+    ico->ret = bdrv_co_invalidate_cache(ico->bs, ico->errp);
     ico->done = true;
     aio_wait_kick();
 }
 
-void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
+int bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
 {
     Coroutine *co;
     InvalidateCacheCo ico = {
@@ -5752,22 +5755,23 @@ void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
         bdrv_coroutine_enter(bs, co);
         BDRV_POLL_WHILE(bs, !ico.done);
     }
+
+    return ico.ret;
 }
 
 void bdrv_invalidate_cache_all(Error **errp)
 {
     BlockDriverState *bs;
-    Error *local_err = NULL;
     BdrvNextIterator it;
 
     for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
         AioContext *aio_context = bdrv_get_aio_context(bs);
+        int ret;
 
         aio_context_acquire(aio_context);
-        bdrv_invalidate_cache(bs, &local_err);
+        ret = bdrv_invalidate_cache(bs, errp);
         aio_context_release(aio_context);
-        if (local_err) {
-            error_propagate(errp, local_err);
+        if (ret < 0) {
             bdrv_next_cleanup(&it);
             return;
         }
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH v7 2/7] block/io: refactor coroutine wrappers
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 1/7] block: return error-code from bdrv_invalidate_cache Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 3/7] block: declare some coroutine functions in block/coroutines.h Vladimir Sementsov-Ogievskiy
                   ` (5 subsequent siblings)
  7 siblings, 0 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

Most of our coroutine wrappers already follow this convention:

We have 'coroutine_fn bdrv_co_<something>(<normal argument list>)' as
the core function, and a wrapper 'bdrv_<something>(<same argument
list>)' which does parameters packing and call bdrv_run_co().

The only outsiders are the bdrv_prwv_co and
bdrv_common_block_status_above wrappers. Let's refactor them to behave
as the others, it simplifies further conversion of coroutine wrappers.

This patch adds indirection layer, but it will be compensated by
further commit, which will drop bdrv_co_prwv together with is_write
logic, to keep read and write path separate.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 block/io.c | 60 +++++++++++++++++++++++++++++-------------------------
 1 file changed, 32 insertions(+), 28 deletions(-)

diff --git a/block/io.c b/block/io.c
index df8f2a98d4..af6cb839bf 100644
--- a/block/io.c
+++ b/block/io.c
@@ -933,27 +933,31 @@ typedef struct RwCo {
     BdrvRequestFlags flags;
 } RwCo;
 
+static int coroutine_fn bdrv_co_prwv(BdrvChild *child, int64_t offset,
+                                     QEMUIOVector *qiov, bool is_write,
+                                     BdrvRequestFlags flags)
+{
+    if (is_write) {
+        return bdrv_co_pwritev(child, offset, qiov->size, qiov, flags);
+    } else {
+        return bdrv_co_preadv(child, offset, qiov->size, qiov, flags);
+    }
+}
+
 static int coroutine_fn bdrv_rw_co_entry(void *opaque)
 {
     RwCo *rwco = opaque;
 
-    if (!rwco->is_write) {
-        return bdrv_co_preadv(rwco->child, rwco->offset,
-                              rwco->qiov->size, rwco->qiov,
-                              rwco->flags);
-    } else {
-        return bdrv_co_pwritev(rwco->child, rwco->offset,
-                               rwco->qiov->size, rwco->qiov,
-                               rwco->flags);
-    }
+    return bdrv_co_prwv(rwco->child, rwco->offset, rwco->qiov,
+                        rwco->is_write, rwco->flags);
 }
 
 /*
  * Process a vectored synchronous request using coroutines
  */
-static int bdrv_prwv_co(BdrvChild *child, int64_t offset,
-                        QEMUIOVector *qiov, bool is_write,
-                        BdrvRequestFlags flags)
+static int bdrv_prwv(BdrvChild *child, int64_t offset,
+                     QEMUIOVector *qiov, bool is_write,
+                     BdrvRequestFlags flags)
 {
     RwCo rwco = {
         .child = child,
@@ -971,8 +975,7 @@ int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
 {
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes);
 
-    return bdrv_prwv_co(child, offset, &qiov, true,
-                        BDRV_REQ_ZERO_WRITE | flags);
+    return bdrv_prwv(child, offset, &qiov, true, BDRV_REQ_ZERO_WRITE | flags);
 }
 
 /*
@@ -1021,7 +1024,7 @@ int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov)
 {
     int ret;
 
-    ret = bdrv_prwv_co(child, offset, qiov, false, 0);
+    ret = bdrv_prwv(child, offset, qiov, false, 0);
     if (ret < 0) {
         return ret;
     }
@@ -1045,7 +1048,7 @@ int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov)
 {
     int ret;
 
-    ret = bdrv_prwv_co(child, offset, qiov, true, 0);
+    ret = bdrv_prwv(child, offset, qiov, true, 0);
     if (ret < 0) {
         return ret;
     }
@@ -2463,14 +2466,15 @@ early_out:
     return ret;
 }
 
-static int coroutine_fn bdrv_co_block_status_above(BlockDriverState *bs,
-                                                   BlockDriverState *base,
-                                                   bool want_zero,
-                                                   int64_t offset,
-                                                   int64_t bytes,
-                                                   int64_t *pnum,
-                                                   int64_t *map,
-                                                   BlockDriverState **file)
+static int coroutine_fn
+bdrv_co_common_block_status_above(BlockDriverState *bs,
+                                  BlockDriverState *base,
+                                  bool want_zero,
+                                  int64_t offset,
+                                  int64_t bytes,
+                                  int64_t *pnum,
+                                  int64_t *map,
+                                  BlockDriverState **file)
 {
     BlockDriverState *p;
     int ret = 0;
@@ -2508,10 +2512,10 @@ static int coroutine_fn bdrv_block_status_above_co_entry(void *opaque)
 {
     BdrvCoBlockStatusData *data = opaque;
 
-    return bdrv_co_block_status_above(data->bs, data->base,
-                                      data->want_zero,
-                                      data->offset, data->bytes,
-                                      data->pnum, data->map, data->file);
+    return bdrv_co_common_block_status_above(data->bs, data->base,
+                                             data->want_zero,
+                                             data->offset, data->bytes,
+                                             data->pnum, data->map, data->file);
 }
 
 /*
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH v7 3/7] block: declare some coroutine functions in block/coroutines.h
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 1/7] block: return error-code from bdrv_invalidate_cache Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 2/7] block/io: refactor coroutine wrappers Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 4/7] scripts: add coroutine-wrapper.py Vladimir Sementsov-Ogievskiy
                   ` (4 subsequent siblings)
  7 siblings, 0 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

We are going to keep coroutine-wrappers code (structure-packing
parameters, BDRV_POLL wrapper functions) in separate auto-generated
files. So, we'll need a header with declaration of original _co_
functions, for those which are static now. As well, we'll need
declarations for wrapper functions. Do these declarations now, as a
preparation step.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 block/coroutines.h | 67 ++++++++++++++++++++++++++++++++++++++++++++++
 block.c            |  8 +++---
 block/io.c         | 34 +++++++++++------------
 3 files changed, 88 insertions(+), 21 deletions(-)
 create mode 100644 block/coroutines.h

diff --git a/block/coroutines.h b/block/coroutines.h
new file mode 100644
index 0000000000..9ce1730a09
--- /dev/null
+++ b/block/coroutines.h
@@ -0,0 +1,67 @@
+/*
+ * Block layer I/O functions
+ *
+ * Copyright (c) 2003 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef BLOCK_COROUTINES_INT_H
+#define BLOCK_COROUTINES_INT_H
+
+#include "block/block_int.h"
+
+int coroutine_fn bdrv_co_check(BlockDriverState *bs,
+                               BdrvCheckResult *res, BdrvCheckMode fix);
+int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp);
+
+int coroutine_fn
+bdrv_co_prwv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov,
+             bool is_write, BdrvRequestFlags flags);
+int
+bdrv_prwv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov,
+          bool is_write, BdrvRequestFlags flags);
+
+int coroutine_fn
+bdrv_co_common_block_status_above(BlockDriverState *bs,
+                                  BlockDriverState *base,
+                                  bool want_zero,
+                                  int64_t offset,
+                                  int64_t bytes,
+                                  int64_t *pnum,
+                                  int64_t *map,
+                                  BlockDriverState **file);
+int
+bdrv_common_block_status_above(BlockDriverState *bs,
+                               BlockDriverState *base,
+                               bool want_zero,
+                               int64_t offset,
+                               int64_t bytes,
+                               int64_t *pnum,
+                               int64_t *map,
+                               BlockDriverState **file);
+
+int coroutine_fn
+bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
+                   bool is_read);
+int
+bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
+                bool is_read);
+
+#endif /* BLOCK_COROUTINES_INT_H */
diff --git a/block.c b/block.c
index b01551f21c..2ca9267729 100644
--- a/block.c
+++ b/block.c
@@ -48,6 +48,7 @@
 #include "qemu/timer.h"
 #include "qemu/cutils.h"
 #include "qemu/id.h"
+#include "block/coroutines.h"
 
 #ifdef CONFIG_BSD
 #include <sys/ioctl.h>
@@ -4625,8 +4626,8 @@ static void bdrv_delete(BlockDriverState *bs)
  * free of errors) or -errno when an internal error occurred. The results of the
  * check are stored in res.
  */
-static int coroutine_fn bdrv_co_check(BlockDriverState *bs,
-                                      BdrvCheckResult *res, BdrvCheckMode fix)
+int coroutine_fn bdrv_co_check(BlockDriverState *bs,
+                               BdrvCheckResult *res, BdrvCheckMode fix)
 {
     if (bs->drv == NULL) {
         return -ENOMEDIUM;
@@ -5643,8 +5644,7 @@ void bdrv_init_with_whitelist(void)
     bdrv_init();
 }
 
-static int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
-                                                 Error **errp)
+int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp)
 {
     BdrvChild *child, *parent;
     uint64_t perm, shared_perm;
diff --git a/block/io.c b/block/io.c
index af6cb839bf..deb9ca8d82 100644
--- a/block/io.c
+++ b/block/io.c
@@ -29,6 +29,7 @@
 #include "block/blockjob.h"
 #include "block/blockjob_int.h"
 #include "block/block_int.h"
+#include "block/coroutines.h"
 #include "qemu/cutils.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
@@ -933,9 +934,9 @@ typedef struct RwCo {
     BdrvRequestFlags flags;
 } RwCo;
 
-static int coroutine_fn bdrv_co_prwv(BdrvChild *child, int64_t offset,
-                                     QEMUIOVector *qiov, bool is_write,
-                                     BdrvRequestFlags flags)
+int coroutine_fn bdrv_co_prwv(BdrvChild *child, int64_t offset,
+                              QEMUIOVector *qiov, bool is_write,
+                              BdrvRequestFlags flags)
 {
     if (is_write) {
         return bdrv_co_pwritev(child, offset, qiov->size, qiov, flags);
@@ -955,9 +956,9 @@ static int coroutine_fn bdrv_rw_co_entry(void *opaque)
 /*
  * Process a vectored synchronous request using coroutines
  */
-static int bdrv_prwv(BdrvChild *child, int64_t offset,
-                     QEMUIOVector *qiov, bool is_write,
-                     BdrvRequestFlags flags)
+int bdrv_prwv(BdrvChild *child, int64_t offset,
+              QEMUIOVector *qiov, bool is_write,
+              BdrvRequestFlags flags)
 {
     RwCo rwco = {
         .child = child,
@@ -2466,7 +2467,7 @@ early_out:
     return ret;
 }
 
-static int coroutine_fn
+int coroutine_fn
 bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   BlockDriverState *base,
                                   bool want_zero,
@@ -2523,12 +2524,12 @@ static int coroutine_fn bdrv_block_status_above_co_entry(void *opaque)
  *
  * See bdrv_co_block_status_above() for details.
  */
-static int bdrv_common_block_status_above(BlockDriverState *bs,
-                                          BlockDriverState *base,
-                                          bool want_zero, int64_t offset,
-                                          int64_t bytes, int64_t *pnum,
-                                          int64_t *map,
-                                          BlockDriverState **file)
+int bdrv_common_block_status_above(BlockDriverState *bs,
+                                   BlockDriverState *base,
+                                   bool want_zero, int64_t offset,
+                                   int64_t bytes, int64_t *pnum,
+                                   int64_t *map,
+                                   BlockDriverState **file)
 {
     BdrvCoBlockStatusData data = {
         .bs = bs,
@@ -2644,7 +2645,7 @@ typedef struct BdrvVmstateCo {
     bool                is_read;
 } BdrvVmstateCo;
 
-static int coroutine_fn
+int coroutine_fn
 bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
                    bool is_read)
 {
@@ -2676,9 +2677,8 @@ static int coroutine_fn bdrv_co_rw_vmstate_entry(void *opaque)
     return bdrv_co_rw_vmstate(co->bs, co->qiov, co->pos, co->is_read);
 }
 
-static inline int
-bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
-                bool is_read)
+int bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
+                    bool is_read)
 {
     BdrvVmstateCo data = {
         .bs         = bs,
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH v7 4/7] scripts: add coroutine-wrapper.py
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
                   ` (2 preceding siblings ...)
  2020-06-10 10:03 ` [PATCH v7 3/7] block: declare some coroutine functions in block/coroutines.h Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-08-20  7:38   ` Paolo Bonzini
  2020-06-10 10:03 ` [PATCH v7 5/7] block: generate coroutine-wrapper code Vladimir Sementsov-Ogievskiy
                   ` (3 subsequent siblings)
  7 siblings, 1 reply; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

We have a very frequent pattern of creating coroutine from function
with several arguments:

  - create structure to pack parameters
  - create _entry function to call original function taking parameters
    from struct
  - do different magic to handle completion: set ret to NOT_DONE or
    EINPROGRESS or use separate bool field
  - fill the struct and create coroutine from _entry function and this
    struct as a parameter
  - do coroutine enter and BDRV_POLL_WHILE loop

Let's reduce code duplication by generating coroutine wrappers.

This patch adds scripts/coroutine-wrapper.py together with some
friends, which will generate functions with declared prototypes marked
by 'generated_co_wrapper' specifier.

The usage of new code generation is as follows:

    1. define somewhere

        int coroutine_fn bdrv_co_NAME(...) {...}

       function

    2. declare in some header file

        int generated_co_wrapper bdrv_NAME(...);

       function with same list of parameters. (you'll need to include
       "block/generated-co-wrapper.h" to get the specifier)

    3. both declarations should be available through block/coroutines.h
       header.

    4. add header with generated_co_wrapper declaration into
       COROUTINE_HEADERS list in Makefile

Still, no function is now marked, this work is for the following
commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 Makefile                     |   8 ++
 block/block-gen.h            |  49 ++++++++++
 include/block/block.h        |   7 ++
 block/Makefile.objs          |   1 +
 scripts/coroutine-wrapper.py | 180 +++++++++++++++++++++++++++++++++++
 5 files changed, 245 insertions(+)
 create mode 100644 block/block-gen.h
 create mode 100755 scripts/coroutine-wrapper.py

diff --git a/Makefile b/Makefile
index d1af126ea1..517a29810f 100644
--- a/Makefile
+++ b/Makefile
@@ -175,6 +175,14 @@ generated-files-y += $(TRACE_SOURCES)
 generated-files-y += $(BUILD_DIR)/trace-events-all
 generated-files-y += .git-submodule-status
 
+generated-files-y += block/block-gen.c
+
+COROUTINE_HEADERS = include/block/block.h block/coroutines.h
+block/block-gen.c: $(COROUTINE_HEADERS) scripts/coroutine-wrapper.py
+	$(call quiet-command, \
+		cat $(addprefix $(SRC_PATH)/,$(COROUTINE_HEADERS)) | \
+		$(SRC_PATH)/scripts/coroutine-wrapper.py > $@,"GEN","$(TARGET_DIR)$@")
+
 trace-group-name = $(shell dirname $1 | sed -e 's/[^a-zA-Z0-9]/_/g')
 
 tracetool-y = $(SRC_PATH)/scripts/tracetool.py
diff --git a/block/block-gen.h b/block/block-gen.h
new file mode 100644
index 0000000000..f80cf4897d
--- /dev/null
+++ b/block/block-gen.h
@@ -0,0 +1,49 @@
+/*
+ * Block coroutine wrapping core, used by auto-generated block/block-gen.c
+ *
+ * Copyright (c) 2003 Fabrice Bellard
+ * Copyright (c) 2020 Virtuozzo International GmbH
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef BLOCK_BLOCK_GEN_H
+#define BLOCK_BLOCK_GEN_H
+
+#include "block/block_int.h"
+
+/* Base structure for argument packing structures */
+typedef struct BdrvPollCo {
+    BlockDriverState *bs;
+    bool in_progress;
+    int ret;
+    Coroutine *co; /* Keep pointer here for debugging */
+} BdrvPollCo;
+
+static inline int bdrv_poll_co(BdrvPollCo *s)
+{
+    assert(!qemu_in_coroutine());
+
+    bdrv_coroutine_enter(s->bs, s->co);
+    BDRV_POLL_WHILE(s->bs, s->in_progress);
+
+    return s->ret;
+}
+
+#endif /* BLOCK_BLOCK_GEN_H */
diff --git a/include/block/block.h b/include/block/block.h
index 46965a7780..59a002e06f 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -10,6 +10,13 @@
 #include "block/blockjob.h"
 #include "qemu/hbitmap.h"
 
+/*
+ * generated_co_wrapper
+ * Function specifier, which does nothing but marking functions to be
+ * generated by scripts/coroutine-wrapper.py
+ */
+#define generated_co_wrapper
+
 /* block.c */
 typedef struct BlockDriver BlockDriver;
 typedef struct BdrvChild BdrvChild;
diff --git a/block/Makefile.objs b/block/Makefile.objs
index 3635b6b4c1..05e4d033c1 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -45,6 +45,7 @@ block-obj-y += crypto.o
 block-obj-y += aio_task.o
 block-obj-y += backup-top.o
 block-obj-y += filter-compress.o
+block-obj-y += block-gen.o
 common-obj-y += monitor/
 
 block-obj-y += stream.o
diff --git a/scripts/coroutine-wrapper.py b/scripts/coroutine-wrapper.py
new file mode 100755
index 0000000000..57ae6aed20
--- /dev/null
+++ b/scripts/coroutine-wrapper.py
@@ -0,0 +1,180 @@
+#!/usr/bin/env python3
+"""Generate coroutine wrappers for block subsystem.
+
+The program parses one or several concatenated c files from stdin,
+searches for functions with 'generated_co_wrapper' specifier
+and generates corresponding wrappers on stdout.
+
+Usage: cat FILE.[ch]... | coroutine-wrapper.py > generated-file.c
+
+Copyright (c) 2020 Virtuozzo International GmbH.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+import sys
+import re
+import subprocess
+import json
+from typing import Iterator
+
+
+def prettify(code: str) -> str:
+    """Prettify code using clang-format if available"""
+
+    try:
+        style = json.dumps({
+            'IndentWidth': 4,
+            'BraceWrapping': {'AfterFunction': True},
+            'BreakBeforeBraces': 'Custom',
+            'SortIncludes': False,
+            'MaxEmptyLinesToKeep': 2
+        })
+        p = subprocess.run(['clang-format', f'-style={style}'], check=True,
+                           encoding='utf-8', input=code,
+                           stdout=subprocess.PIPE)
+        return p.stdout
+    except FileNotFoundError:
+        return code
+
+
+def gen_header():
+    copyright = re.sub('^.*Copyright', 'Copyright', __doc__, flags=re.DOTALL)
+    copyright = re.sub('^(?=.)', ' * ', copyright.strip(), flags=re.MULTILINE)
+    copyright = re.sub('^$', ' *', copyright, flags=re.MULTILINE)
+    return f"""\
+/*
+ * File is generated by scripts/coroutine-wrapper.py
+ *
+{copyright}
+ */
+
+#include "qemu/osdep.h"
+#include "block/coroutines.h"
+#include "block/block-gen.h"
+#include "block/block_int.h"\
+"""
+
+
+class ParamDecl:
+    param_re = re.compile(r'(?P<decl>'
+                          r'(?P<type>.*[ *])'
+                          r'(?P<name>[a-z][a-z0-9_]*)'
+                          r')')
+
+    def __init__(self, param_decl: str) -> None:
+        m = self.param_re.match(param_decl.strip())
+        if m is None:
+            raise ValueError(f'Wrong parameter declaration: "{param_decl}"')
+        self.decl = m.group('decl')
+        self.type = m.group('type')
+        self.name = m.group('name')
+
+
+class FuncDecl:
+    def __init__(self, return_type: str, name: str, args: str) -> None:
+        self.return_type = return_type.strip()
+        self.name = name.strip()
+        self.args = [ParamDecl(arg.strip()) for arg in args.split(',')]
+
+    def gen_list(self, format: str) -> str:
+        return ', '.join(format.format_map(arg.__dict__) for arg in self.args)
+
+    def gen_block(self, format: str) -> str:
+        return '\n'.join(format.format_map(arg.__dict__) for arg in self.args)
+
+
+# Match wrappers declared with a generated_co_wrapper mark
+func_decl_re = re.compile(r'^int\s*generated_co_wrapper\s*'
+                          r'(?P<wrapper_name>[a-z][a-z0-9_]*)'
+                          r'\((?P<args>[^)]*)\);$', re.MULTILINE)
+
+
+def func_decl_iter(text: str) -> Iterator:
+    for m in func_decl_re.finditer(text):
+        yield FuncDecl(return_type='int',
+                       name=m.group('wrapper_name'),
+                       args=m.group('args'))
+
+
+def snake_to_camel(func_name: str) -> str:
+    """
+    Convert underscore names like 'some_function_name' to camel-case like
+    'SomeFunctionName'
+    """
+    words = func_name.split('_')
+    words = [w[0].upper() + w[1:] for w in words]
+    return ''.join(words)
+
+
+def gen_wrapper(func: FuncDecl) -> str:
+    assert func.name.startswith('bdrv_')
+    assert not func.name.startswith('bdrv_co_')
+    assert func.return_type == 'int'
+    assert func.args[0].type in ['BlockDriverState *', 'BdrvChild *']
+
+    name = 'bdrv_co_' + func.name[5:]
+    bs = 'bs' if func.args[0].type == 'BlockDriverState *' else 'child->bs'
+    struct_name = snake_to_camel(name)
+
+    return f"""\
+/*
+ * Wrappers for {name}
+ */
+
+typedef struct {struct_name} {{
+    BdrvPollCo poll_state;
+{ func.gen_block('    {decl};') }
+}} {struct_name};
+
+static void coroutine_fn {name}_entry(void *opaque)
+{{
+    {struct_name} *s = opaque;
+
+    s->poll_state.ret = {name}({ func.gen_list('s->{name}') });
+    s->poll_state.in_progress = false;
+
+    aio_wait_kick();
+}}
+
+int {func.name}({ func.gen_list('{decl}') })
+{{
+    if (qemu_in_coroutine()) {{
+        return {name}({ func.gen_list('{name}') });
+    }} else {{
+        {struct_name} s = {{
+            .poll_state.bs = {bs},
+            .poll_state.in_progress = true,
+
+{ func.gen_block('            .{name} = {name},') }
+        }};
+
+        s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
+
+        return bdrv_poll_co(&s.poll_state);
+    }}
+}}"""
+
+
+def gen_wrappers_file(input_code: str) -> str:
+    res = gen_header()
+    for func in func_decl_iter(input_code):
+        res += '\n\n\n'
+        res += gen_wrapper(func)
+
+    return prettify(res)  # prettify to wrap long lines
+
+
+if __name__ == '__main__':
+    print(gen_wrappers_file(sys.stdin.read()))
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH v7 5/7] block: generate coroutine-wrapper code
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
                   ` (3 preceding siblings ...)
  2020-06-10 10:03 ` [PATCH v7 4/7] scripts: add coroutine-wrapper.py Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 6/7] block: drop bdrv_prwv Vladimir Sementsov-Ogievskiy
                   ` (2 subsequent siblings)
  7 siblings, 0 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

Use code generation implemented in previous commit to generated
coroutine wrappers in block.c and block/io.c

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 block/coroutines.h    |   6 +-
 include/block/block.h |  16 ++--
 block.c               |  73 ---------------
 block/io.c            | 212 ------------------------------------------
 4 files changed, 13 insertions(+), 294 deletions(-)

diff --git a/block/coroutines.h b/block/coroutines.h
index 9ce1730a09..c62b3a2697 100644
--- a/block/coroutines.h
+++ b/block/coroutines.h
@@ -34,7 +34,7 @@ int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp);
 int coroutine_fn
 bdrv_co_prwv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov,
              bool is_write, BdrvRequestFlags flags);
-int
+int generated_co_wrapper
 bdrv_prwv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov,
           bool is_write, BdrvRequestFlags flags);
 
@@ -47,7 +47,7 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   int64_t *pnum,
                                   int64_t *map,
                                   BlockDriverState **file);
-int
+int generated_co_wrapper
 bdrv_common_block_status_above(BlockDriverState *bs,
                                BlockDriverState *base,
                                bool want_zero,
@@ -60,7 +60,7 @@ bdrv_common_block_status_above(BlockDriverState *bs,
 int coroutine_fn
 bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
                    bool is_read);
-int
+int generated_co_wrapper
 bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
                 bool is_read);
 
diff --git a/include/block/block.h b/include/block/block.h
index 59a002e06f..9f94c59057 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -405,8 +405,9 @@ void bdrv_refresh_filename(BlockDriverState *bs);
 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, bool exact,
                                   PreallocMode prealloc, BdrvRequestFlags flags,
                                   Error **errp);
-int bdrv_truncate(BdrvChild *child, int64_t offset, bool exact,
-                  PreallocMode prealloc, BdrvRequestFlags flags, Error **errp);
+int generated_co_wrapper
+bdrv_truncate(BdrvChild *child, int64_t offset, bool exact,
+              PreallocMode prealloc, BdrvRequestFlags flags, Error **errp);
 
 int64_t bdrv_nb_sectors(BlockDriverState *bs);
 int64_t bdrv_getlength(BlockDriverState *bs);
@@ -448,7 +449,8 @@ typedef enum {
     BDRV_FIX_ERRORS   = 2,
 } BdrvCheckMode;
 
-int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
+int generated_co_wrapper bdrv_check(BlockDriverState *bs, BdrvCheckResult *res,
+                                    BdrvCheckMode fix);
 
 /* The units of offset and total_work_size may be chosen arbitrarily by the
  * block driver; total_work_size may change during the course of the amendment
@@ -471,12 +473,13 @@ void bdrv_aio_cancel_async(BlockAIOCB *acb);
 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
 
 /* Invalidate any cached metadata used by image formats */
-int bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
+int generated_co_wrapper bdrv_invalidate_cache(BlockDriverState *bs,
+                                               Error **errp);
 void bdrv_invalidate_cache_all(Error **errp);
 int bdrv_inactivate_all(void);
 
 /* Ensure contents are flushed to disk.  */
-int bdrv_flush(BlockDriverState *bs);
+int generated_co_wrapper bdrv_flush(BlockDriverState *bs);
 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
 int bdrv_flush_all(void);
 void bdrv_close_all(void);
@@ -491,7 +494,8 @@ void bdrv_drain_all(void);
     AIO_WAIT_WHILE(bdrv_get_aio_context(bs_),              \
                    cond); })
 
-int bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes);
+int generated_co_wrapper bdrv_pdiscard(BdrvChild *child, int64_t offset,
+                                       int64_t bytes);
 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes);
 int bdrv_has_zero_init_1(BlockDriverState *bs);
 int bdrv_has_zero_init(BlockDriverState *bs);
diff --git a/block.c b/block.c
index 2ca9267729..3046696f30 100644
--- a/block.c
+++ b/block.c
@@ -4640,43 +4640,6 @@ int coroutine_fn bdrv_co_check(BlockDriverState *bs,
     return bs->drv->bdrv_co_check(bs, res, fix);
 }
 
-typedef struct CheckCo {
-    BlockDriverState *bs;
-    BdrvCheckResult *res;
-    BdrvCheckMode fix;
-    int ret;
-} CheckCo;
-
-static void coroutine_fn bdrv_check_co_entry(void *opaque)
-{
-    CheckCo *cco = opaque;
-    cco->ret = bdrv_co_check(cco->bs, cco->res, cco->fix);
-    aio_wait_kick();
-}
-
-int bdrv_check(BlockDriverState *bs,
-               BdrvCheckResult *res, BdrvCheckMode fix)
-{
-    Coroutine *co;
-    CheckCo cco = {
-        .bs = bs,
-        .res = res,
-        .ret = -EINPROGRESS,
-        .fix = fix,
-    };
-
-    if (qemu_in_coroutine()) {
-        /* Fast-path if already in coroutine context */
-        bdrv_check_co_entry(&cco);
-    } else {
-        co = qemu_coroutine_create(bdrv_check_co_entry, &cco);
-        bdrv_coroutine_enter(bs, co);
-        BDRV_POLL_WHILE(bs, cco.ret == -EINPROGRESS);
-    }
-
-    return cco.ret;
-}
-
 /*
  * Return values:
  * 0        - success
@@ -5723,42 +5686,6 @@ int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp)
     return 0;
 }
 
-typedef struct InvalidateCacheCo {
-    BlockDriverState *bs;
-    Error **errp;
-    bool done;
-    int ret;
-} InvalidateCacheCo;
-
-static void coroutine_fn bdrv_invalidate_cache_co_entry(void *opaque)
-{
-    InvalidateCacheCo *ico = opaque;
-    ico->ret = bdrv_co_invalidate_cache(ico->bs, ico->errp);
-    ico->done = true;
-    aio_wait_kick();
-}
-
-int bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
-{
-    Coroutine *co;
-    InvalidateCacheCo ico = {
-        .bs = bs,
-        .done = false,
-        .errp = errp
-    };
-
-    if (qemu_in_coroutine()) {
-        /* Fast-path if already in coroutine context */
-        bdrv_invalidate_cache_co_entry(&ico);
-    } else {
-        co = qemu_coroutine_create(bdrv_invalidate_cache_co_entry, &ico);
-        bdrv_coroutine_enter(bs, co);
-        BDRV_POLL_WHILE(bs, !ico.done);
-    }
-
-    return ico.ret;
-}
-
 void bdrv_invalidate_cache_all(Error **errp)
 {
     BlockDriverState *bs;
diff --git a/block/io.c b/block/io.c
index deb9ca8d82..36fbf9e1fa 100644
--- a/block/io.c
+++ b/block/io.c
@@ -890,50 +890,6 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
     return 0;
 }
 
-typedef int coroutine_fn BdrvRequestEntry(void *opaque);
-typedef struct BdrvRunCo {
-    BdrvRequestEntry *entry;
-    void *opaque;
-    int ret;
-    bool done;
-    Coroutine *co; /* Coroutine, running bdrv_run_co_entry, for debugging */
-} BdrvRunCo;
-
-static void coroutine_fn bdrv_run_co_entry(void *opaque)
-{
-    BdrvRunCo *arg = opaque;
-
-    arg->ret = arg->entry(arg->opaque);
-    arg->done = true;
-    aio_wait_kick();
-}
-
-static int bdrv_run_co(BlockDriverState *bs, BdrvRequestEntry *entry,
-                       void *opaque)
-{
-    if (qemu_in_coroutine()) {
-        /* Fast-path if already in coroutine context */
-        return entry(opaque);
-    } else {
-        BdrvRunCo s = { .entry = entry, .opaque = opaque };
-
-        s.co = qemu_coroutine_create(bdrv_run_co_entry, &s);
-        bdrv_coroutine_enter(bs, s.co);
-
-        BDRV_POLL_WHILE(bs, !s.done);
-
-        return s.ret;
-    }
-}
-
-typedef struct RwCo {
-    BdrvChild *child;
-    int64_t offset;
-    QEMUIOVector *qiov;
-    bool is_write;
-    BdrvRequestFlags flags;
-} RwCo;
-
 int coroutine_fn bdrv_co_prwv(BdrvChild *child, int64_t offset,
                               QEMUIOVector *qiov, bool is_write,
                               BdrvRequestFlags flags)
@@ -945,32 +901,6 @@ int coroutine_fn bdrv_co_prwv(BdrvChild *child, int64_t offset,
     }
 }
 
-static int coroutine_fn bdrv_rw_co_entry(void *opaque)
-{
-    RwCo *rwco = opaque;
-
-    return bdrv_co_prwv(rwco->child, rwco->offset, rwco->qiov,
-                        rwco->is_write, rwco->flags);
-}
-
-/*
- * Process a vectored synchronous request using coroutines
- */
-int bdrv_prwv(BdrvChild *child, int64_t offset,
-              QEMUIOVector *qiov, bool is_write,
-              BdrvRequestFlags flags)
-{
-    RwCo rwco = {
-        .child = child,
-        .offset = offset,
-        .qiov = qiov,
-        .is_write = is_write,
-        .flags = flags,
-    };
-
-    return bdrv_run_co(child->bs, bdrv_rw_co_entry, &rwco);
-}
-
 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
                        int bytes, BdrvRequestFlags flags)
 {
@@ -2245,18 +2175,6 @@ int bdrv_flush_all(void)
     return result;
 }
 
-
-typedef struct BdrvCoBlockStatusData {
-    BlockDriverState *bs;
-    BlockDriverState *base;
-    bool want_zero;
-    int64_t offset;
-    int64_t bytes;
-    int64_t *pnum;
-    int64_t *map;
-    BlockDriverState **file;
-} BdrvCoBlockStatusData;
-
 int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs,
                                                 bool want_zero,
                                                 int64_t offset,
@@ -2508,43 +2426,6 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
     return ret;
 }
 
-/* Coroutine wrapper for bdrv_block_status_above() */
-static int coroutine_fn bdrv_block_status_above_co_entry(void *opaque)
-{
-    BdrvCoBlockStatusData *data = opaque;
-
-    return bdrv_co_common_block_status_above(data->bs, data->base,
-                                             data->want_zero,
-                                             data->offset, data->bytes,
-                                             data->pnum, data->map, data->file);
-}
-
-/*
- * Synchronous wrapper around bdrv_co_block_status_above().
- *
- * See bdrv_co_block_status_above() for details.
- */
-int bdrv_common_block_status_above(BlockDriverState *bs,
-                                   BlockDriverState *base,
-                                   bool want_zero, int64_t offset,
-                                   int64_t bytes, int64_t *pnum,
-                                   int64_t *map,
-                                   BlockDriverState **file)
-{
-    BdrvCoBlockStatusData data = {
-        .bs = bs,
-        .base = base,
-        .want_zero = want_zero,
-        .offset = offset,
-        .bytes = bytes,
-        .pnum = pnum,
-        .map = map,
-        .file = file,
-    };
-
-    return bdrv_run_co(bs, bdrv_block_status_above_co_entry, &data);
-}
-
 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
                             int64_t offset, int64_t bytes, int64_t *pnum,
                             int64_t *map, BlockDriverState **file)
@@ -2638,13 +2519,6 @@ int bdrv_is_allocated_above(BlockDriverState *top,
     return 0;
 }
 
-typedef struct BdrvVmstateCo {
-    BlockDriverState    *bs;
-    QEMUIOVector        *qiov;
-    int64_t             pos;
-    bool                is_read;
-} BdrvVmstateCo;
-
 int coroutine_fn
 bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
                    bool is_read)
@@ -2670,26 +2544,6 @@ bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
     return ret;
 }
 
-static int coroutine_fn bdrv_co_rw_vmstate_entry(void *opaque)
-{
-    BdrvVmstateCo *co = opaque;
-
-    return bdrv_co_rw_vmstate(co->bs, co->qiov, co->pos, co->is_read);
-}
-
-int bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
-                    bool is_read)
-{
-    BdrvVmstateCo data = {
-        .bs         = bs,
-        .qiov       = qiov,
-        .pos        = pos,
-        .is_read    = is_read,
-    };
-
-    return bdrv_run_co(bs, bdrv_co_rw_vmstate_entry, &data);
-}
-
 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
                       int64_t pos, int size)
 {
@@ -2765,11 +2619,6 @@ void bdrv_aio_cancel_async(BlockAIOCB *acb)
 /**************************************************************/
 /* Coroutine block device emulation */
 
-static int coroutine_fn bdrv_flush_co_entry(void *opaque)
-{
-    return bdrv_co_flush(opaque);
-}
-
 int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
 {
     int current_gen;
@@ -2882,24 +2731,6 @@ early_exit:
     return ret;
 }
 
-int bdrv_flush(BlockDriverState *bs)
-{
-    return bdrv_run_co(bs, bdrv_flush_co_entry, bs);
-}
-
-typedef struct DiscardCo {
-    BdrvChild *child;
-    int64_t offset;
-    int64_t bytes;
-} DiscardCo;
-
-static int coroutine_fn bdrv_pdiscard_co_entry(void *opaque)
-{
-    DiscardCo *rwco = opaque;
-
-    return bdrv_co_pdiscard(rwco->child, rwco->offset, rwco->bytes);
-}
-
 int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset,
                                   int64_t bytes)
 {
@@ -3014,17 +2845,6 @@ out:
     return ret;
 }
 
-int bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes)
-{
-    DiscardCo rwco = {
-        .child = child,
-        .offset = offset,
-        .bytes = bytes,
-    };
-
-    return bdrv_run_co(child->bs, bdrv_pdiscard_co_entry, &rwco);
-}
-
 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf)
 {
     BlockDriver *drv = bs->drv;
@@ -3422,35 +3242,3 @@ out:
 
     return ret;
 }
-
-typedef struct TruncateCo {
-    BdrvChild *child;
-    int64_t offset;
-    bool exact;
-    PreallocMode prealloc;
-    BdrvRequestFlags flags;
-    Error **errp;
-} TruncateCo;
-
-static int coroutine_fn bdrv_truncate_co_entry(void *opaque)
-{
-    TruncateCo *tco = opaque;
-
-    return bdrv_co_truncate(tco->child, tco->offset, tco->exact,
-                            tco->prealloc, tco->flags, tco->errp);
-}
-
-int bdrv_truncate(BdrvChild *child, int64_t offset, bool exact,
-                  PreallocMode prealloc, BdrvRequestFlags flags, Error **errp)
-{
-    TruncateCo tco = {
-        .child      = child,
-        .offset     = offset,
-        .exact      = exact,
-        .prealloc   = prealloc,
-        .flags      = flags,
-        .errp       = errp,
-    };
-
-    return bdrv_run_co(child->bs, bdrv_truncate_co_entry, &tco);
-}
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH v7 6/7] block: drop bdrv_prwv
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
                   ` (4 preceding siblings ...)
  2020-06-10 10:03 ` [PATCH v7 5/7] block: generate coroutine-wrapper code Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-06-10 10:03 ` [PATCH v7 7/7] block/io: refactor save/load vmstate Vladimir Sementsov-Ogievskiy
  2020-07-27 12:48 ` [PATCH v7 0/7] coroutines: generate wrapper code Stefan Hajnoczi
  7 siblings, 0 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

Now that we are not maintaining boilerplate code for coroutine
wrappers, there is no more sense in keeping the extra indirection layer
of bdrv_prwv().  Let's drop it and instead generate pure bdrv_preadv()
and bdrv_pwritev().

Currently, bdrv_pwritev() and bdrv_preadv() are returning bytes on
success, auto generated functions will instead return zero, as their
_co_ prototype. Still, it's simple to make the conversion safe: the
only external user of bdrv_pwritev() is test-bdrv-drain, and it is
comfortable enough with bdrv_co_pwritev() instead. So prototypes are
moved to local block/coroutines.h. Next, the only internal use is
bdrv_pread() and bdrv_pwrite(), which are modified to return bytes on
success.

Of course, it would be great to convert bdrv_pread() and bdrv_pwrite()
to return 0 on success. But this requires audit (and probably
conversion) of all their users, let's leave it for another day
refactoring.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 block/coroutines.h      | 10 ++++-----
 include/block/block.h   |  2 --
 block/io.c              | 49 ++++++++---------------------------------
 tests/test-bdrv-drain.c |  2 +-
 4 files changed, 15 insertions(+), 48 deletions(-)

diff --git a/block/coroutines.h b/block/coroutines.h
index c62b3a2697..6c63a819c9 100644
--- a/block/coroutines.h
+++ b/block/coroutines.h
@@ -31,12 +31,12 @@ int coroutine_fn bdrv_co_check(BlockDriverState *bs,
                                BdrvCheckResult *res, BdrvCheckMode fix);
 int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp);
 
-int coroutine_fn
-bdrv_co_prwv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov,
-             bool is_write, BdrvRequestFlags flags);
 int generated_co_wrapper
-bdrv_prwv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov,
-          bool is_write, BdrvRequestFlags flags);
+bdrv_preadv(BdrvChild *child, int64_t offset, unsigned int bytes,
+            QEMUIOVector *qiov, BdrvRequestFlags flags);
+int generated_co_wrapper
+bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes,
+             QEMUIOVector *qiov, BdrvRequestFlags flags);
 
 int coroutine_fn
 bdrv_co_common_block_status_above(BlockDriverState *bs,
diff --git a/include/block/block.h b/include/block/block.h
index 9f94c59057..280cf2a7d5 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -385,9 +385,7 @@ int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
                        int bytes, BdrvRequestFlags flags);
 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags);
 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes);
-int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov);
 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes);
-int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov);
 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset,
                      const void *buf, int count);
 /*
diff --git a/block/io.c b/block/io.c
index 36fbf9e1fa..3060c7e6ed 100644
--- a/block/io.c
+++ b/block/io.c
@@ -890,23 +890,11 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
     return 0;
 }
 
-int coroutine_fn bdrv_co_prwv(BdrvChild *child, int64_t offset,
-                              QEMUIOVector *qiov, bool is_write,
-                              BdrvRequestFlags flags)
-{
-    if (is_write) {
-        return bdrv_co_pwritev(child, offset, qiov->size, qiov, flags);
-    } else {
-        return bdrv_co_preadv(child, offset, qiov->size, qiov, flags);
-    }
-}
-
 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
                        int bytes, BdrvRequestFlags flags)
 {
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes);
-
-    return bdrv_prwv(child, offset, &qiov, true, BDRV_REQ_ZERO_WRITE | flags);
+    return bdrv_pwritev(child, offset, bytes, NULL,
+                        BDRV_REQ_ZERO_WRITE | flags);
 }
 
 /*
@@ -950,41 +938,19 @@ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)
     }
 }
 
-/* return < 0 if error. See bdrv_pwrite() for the return codes */
-int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov)
-{
-    int ret;
-
-    ret = bdrv_prwv(child, offset, qiov, false, 0);
-    if (ret < 0) {
-        return ret;
-    }
-
-    return qiov->size;
-}
-
 /* See bdrv_pwrite() for the return codes */
 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes)
 {
+    int ret;
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
 
     if (bytes < 0) {
         return -EINVAL;
     }
 
-    return bdrv_preadv(child, offset, &qiov);
-}
-
-int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov)
-{
-    int ret;
+    ret = bdrv_preadv(child, offset, bytes, &qiov,  0);
 
-    ret = bdrv_prwv(child, offset, qiov, true, 0);
-    if (ret < 0) {
-        return ret;
-    }
-
-    return qiov->size;
+    return ret < 0 ? ret : bytes;
 }
 
 /* Return no. of bytes on success or < 0 on error. Important errors are:
@@ -995,13 +961,16 @@ int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov)
 */
 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes)
 {
+    int ret;
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
 
     if (bytes < 0) {
         return -EINVAL;
     }
 
-    return bdrv_pwritev(child, offset, &qiov);
+    ret = bdrv_pwritev(child, offset, bytes, &qiov, 0);
+
+    return ret < 0 ? ret : bytes;
 }
 
 /*
diff --git a/tests/test-bdrv-drain.c b/tests/test-bdrv-drain.c
index 1107271840..1595bbc92e 100644
--- a/tests/test-bdrv-drain.c
+++ b/tests/test-bdrv-drain.c
@@ -1872,7 +1872,7 @@ static int coroutine_fn bdrv_replace_test_co_preadv(BlockDriverState *bs,
         }
         s->io_co = NULL;
 
-        ret = bdrv_preadv(bs->backing, offset, qiov);
+        ret = bdrv_co_preadv(bs->backing, offset, bytes, qiov, 0);
         s->has_read = true;
 
         /* Wake up drain_co if it runs */
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* [PATCH v7 7/7] block/io: refactor save/load vmstate
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
                   ` (5 preceding siblings ...)
  2020-06-10 10:03 ` [PATCH v7 6/7] block: drop bdrv_prwv Vladimir Sementsov-Ogievskiy
@ 2020-06-10 10:03 ` Vladimir Sementsov-Ogievskiy
  2020-07-27 12:48 ` [PATCH v7 0/7] coroutines: generate wrapper code Stefan Hajnoczi
  7 siblings, 0 replies; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-06-10 10:03 UTC (permalink / raw)
  To: qemu-block
  Cc: fam, kwolf, vsementsov, ehabkost, qemu-devel, mreitz, stefanha,
	crosa, den

Like for read/write in a previous commit, drop extra indirection layer,
generate directly bdrv_readv_vmstate() and bdrv_writev_vmstate().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 block/coroutines.h    | 10 +++----
 include/block/block.h |  6 ++--
 block/io.c            | 67 ++++++++++++++++++++++---------------------
 3 files changed, 42 insertions(+), 41 deletions(-)

diff --git a/block/coroutines.h b/block/coroutines.h
index 6c63a819c9..f69179f5ef 100644
--- a/block/coroutines.h
+++ b/block/coroutines.h
@@ -57,11 +57,9 @@ bdrv_common_block_status_above(BlockDriverState *bs,
                                int64_t *map,
                                BlockDriverState **file);
 
-int coroutine_fn
-bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
-                   bool is_read);
-int generated_co_wrapper
-bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
-                bool is_read);
+int coroutine_fn bdrv_co_readv_vmstate(BlockDriverState *bs,
+                                       QEMUIOVector *qiov, int64_t pos);
+int coroutine_fn bdrv_co_writev_vmstate(BlockDriverState *bs,
+                                        QEMUIOVector *qiov, int64_t pos);
 
 #endif /* BLOCK_COROUTINES_INT_H */
diff --git a/include/block/block.h b/include/block/block.h
index 280cf2a7d5..7826c3fe27 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -574,8 +574,10 @@ int path_has_protocol(const char *path);
 int path_is_absolute(const char *path);
 char *path_combine(const char *base_path, const char *filename);
 
-int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
-int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
+int generated_co_wrapper
+bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
+int generated_co_wrapper
+bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
                       int64_t pos, int size);
 
diff --git a/block/io.c b/block/io.c
index 3060c7e6ed..83ffc7d390 100644
--- a/block/io.c
+++ b/block/io.c
@@ -2489,66 +2489,67 @@ int bdrv_is_allocated_above(BlockDriverState *top,
 }
 
 int coroutine_fn
-bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
-                   bool is_read)
+bdrv_co_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
 {
     BlockDriver *drv = bs->drv;
     int ret = -ENOTSUP;
 
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+
     bdrv_inc_in_flight(bs);
 
-    if (!drv) {
-        ret = -ENOMEDIUM;
-    } else if (drv->bdrv_load_vmstate) {
-        if (is_read) {
-            ret = drv->bdrv_load_vmstate(bs, qiov, pos);
-        } else {
-            ret = drv->bdrv_save_vmstate(bs, qiov, pos);
-        }
+    if (drv->bdrv_load_vmstate) {
+        ret = drv->bdrv_load_vmstate(bs, qiov, pos);
     } else if (bs->file) {
-        ret = bdrv_co_rw_vmstate(bs->file->bs, qiov, pos, is_read);
+        ret = bdrv_co_readv_vmstate(bs->file->bs, qiov, pos);
     }
 
     bdrv_dec_in_flight(bs);
+
     return ret;
 }
 
-int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
-                      int64_t pos, int size)
+int coroutine_fn
+bdrv_co_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
 {
-    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size);
-    int ret;
+    BlockDriver *drv = bs->drv;
+    int ret = -ENOTSUP;
 
-    ret = bdrv_writev_vmstate(bs, &qiov, pos);
-    if (ret < 0) {
-        return ret;
+    if (!drv) {
+        return -ENOMEDIUM;
     }
 
-    return size;
-}
+    bdrv_inc_in_flight(bs);
 
-int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
-{
-    return bdrv_rw_vmstate(bs, qiov, pos, false);
+    if (drv->bdrv_load_vmstate) {
+        ret = drv->bdrv_save_vmstate(bs, qiov, pos);
+    } else if (bs->file) {
+        ret = bdrv_co_writev_vmstate(bs->file->bs, qiov, pos);
+    }
+
+    bdrv_dec_in_flight(bs);
+
+    return ret;
 }
 
-int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
+int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
                       int64_t pos, int size)
 {
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size);
-    int ret;
-
-    ret = bdrv_readv_vmstate(bs, &qiov, pos);
-    if (ret < 0) {
-        return ret;
-    }
+    int ret = bdrv_writev_vmstate(bs, &qiov, pos);
 
-    return size;
+    return ret < 0 ? ret : size;
 }
 
-int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
+int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
+                      int64_t pos, int size)
 {
-    return bdrv_rw_vmstate(bs, qiov, pos, true);
+    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size);
+    int ret = bdrv_readv_vmstate(bs, &qiov, pos);
+
+    return ret < 0 ? ret : size;
 }
 
 /**************************************************************/
-- 
2.21.0



^ permalink raw reply related	[flat|nested] 13+ messages in thread
* Re: [PATCH v7 0/7] coroutines: generate wrapper code
  2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
                   ` (6 preceding siblings ...)
  2020-06-10 10:03 ` [PATCH v7 7/7] block/io: refactor save/load vmstate Vladimir Sementsov-Ogievskiy
@ 2020-07-27 12:48 ` Stefan Hajnoczi
  2020-07-27 12:59   ` Vladimir Sementsov-Ogievskiy
  7 siblings, 1 reply; 13+ messages in thread
From: Stefan Hajnoczi @ 2020-07-27 12:48 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy
  Cc: fam, kwolf, ehabkost, qemu-block, qemu-devel, mreitz, crosa, den

[-- Attachment #1: Type: text/plain, Size: 647 bytes --]

On Wed, Jun 10, 2020 at 01:03:29PM +0300, Vladimir Sementsov-Ogievskiy wrote:
> Hi all!
> 
> The aim of the series is to reduce code-duplication and writing
> parameters structure-packing by hand around coroutine function wrappers.
> 
> Benefits:
>  - no code duplication
>  - less indirection

Please add documentation so others know when and how to use this.

I suggest adding a docs/devel/coroutine-wrapper.rst document and adding
a code comment to #define generated_co_wrapper pointing to the
documentation.

Please rename coroutine-wrapper.py to block-coroutine-wrapper.py since
it is specific to the block layer.

Stefan

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH v7 0/7] coroutines: generate wrapper code
  2020-07-27 12:48 ` [PATCH v7 0/7] coroutines: generate wrapper code Stefan Hajnoczi
@ 2020-07-27 12:59   ` Vladimir Sementsov-Ogievskiy
  2020-08-20  1:33     ` Eric Blake
  0 siblings, 1 reply; 13+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-27 12:59 UTC (permalink / raw)
  To: Stefan Hajnoczi
  Cc: fam, kwolf, ehabkost, qemu-block, qemu-devel, mreitz, crosa, den

27.07.2020 15:48, Stefan Hajnoczi wrote:
> On Wed, Jun 10, 2020 at 01:03:29PM +0300, Vladimir Sementsov-Ogievskiy wrote:
>> Hi all!
>>
>> The aim of the series is to reduce code-duplication and writing
>> parameters structure-packing by hand around coroutine function wrappers.
>>
>> Benefits:
>>   - no code duplication
>>   - less indirection
> 
> Please add documentation so others know when and how to use this.
> 
> I suggest adding a docs/devel/coroutine-wrapper.rst document and adding
> a code comment to #define generated_co_wrapper pointing to the
> documentation.
> 
> Please rename coroutine-wrapper.py to block-coroutine-wrapper.py since
> it is specific to the block layer.
> 

OK, will do. Thanks for taking a look!


-- 
Best regards,
Vladimir


^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH v7 0/7] coroutines: generate wrapper code
  2020-07-27 12:59   ` Vladimir Sementsov-Ogievskiy
@ 2020-08-20  1:33     ` Eric Blake
  2020-08-20  7:34       ` Paolo Bonzini
  0 siblings, 1 reply; 13+ messages in thread
From: Eric Blake @ 2020-08-20  1:33 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, Stefan Hajnoczi
  Cc: fam, kwolf, ehabkost, qemu-block, qemu-devel, mreitz,
	Paolo Bonzini, crosa, den

On 7/27/20 7:59 AM, Vladimir Sementsov-Ogievskiy wrote:
> 27.07.2020 15:48, Stefan Hajnoczi wrote:
>> On Wed, Jun 10, 2020 at 01:03:29PM +0300, Vladimir Sementsov-Ogievskiy 
>> wrote:
>>> Hi all!
>>>
>>> The aim of the series is to reduce code-duplication and writing
>>> parameters structure-packing by hand around coroutine function wrappers.
>>>
>>> Benefits:
>>>   - no code duplication
>>>   - less indirection
>>
>> Please add documentation so others know when and how to use this.
>>
>> I suggest adding a docs/devel/coroutine-wrapper.rst document and adding
>> a code comment to #define generated_co_wrapper pointing to the
>> documentation.
>>
>> Please rename coroutine-wrapper.py to block-coroutine-wrapper.py since
>> it is specific to the block layer.
>>
> 
> OK, will do. Thanks for taking a look!

As this series touched Makefile to add a generated .c, you'll also need 
to rebase that part to apply on top of Paolo's meson conversion (cc'ing 
him if you need help figuring it out)

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org



^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH v7 0/7] coroutines: generate wrapper code
  2020-08-20  1:33     ` Eric Blake
@ 2020-08-20  7:34       ` Paolo Bonzini
  0 siblings, 0 replies; 13+ messages in thread
From: Paolo Bonzini @ 2020-08-20  7:34 UTC (permalink / raw)
  To: Eric Blake, Vladimir Sementsov-Ogievskiy, Stefan Hajnoczi
  Cc: fam, kwolf, ehabkost, qemu-block, qemu-devel, mreitz, crosa, den

On 20/08/20 03:33, Eric Blake wrote:
>>>
>>
>> OK, will do. Thanks for taking a look!
> 
> As this series touched Makefile to add a generated .c, you'll also need
> to rebase that part to apply on top of Paolo's meson conversion (cc'ing
> him if you need help figuring it out)

It should be trivial to do so using custom_target.

Paolo



^ permalink raw reply	[flat|nested] 13+ messages in thread
* Re: [PATCH v7 4/7] scripts: add coroutine-wrapper.py
  2020-06-10 10:03 ` [PATCH v7 4/7] scripts: add coroutine-wrapper.py Vladimir Sementsov-Ogievskiy
@ 2020-08-20  7:38   ` Paolo Bonzini
  0 siblings, 0 replies; 13+ messages in thread
From: Paolo Bonzini @ 2020-08-20  7:38 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: fam, kwolf, ehabkost, qemu-devel, mreitz, stefanha, crosa, den

On 10/06/20 12:03, Vladimir Sementsov-Ogievskiy wrote:
> +        {struct_name} s = {{
> +            .poll_state.bs = {bs},
> +            .poll_state.in_progress = true,
> +
> +{ func.gen_block('            .{name} = {name},') }
> +        }};
> +
> +        s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
> +
> +        return bdrv_poll_co(&s.poll_state);
> +    }}
> +}}"""
> +
> +
> +def gen_wrappers_file(input_code: str) -> str:
> +    res = gen_header()
> +    for func in func_decl_iter(input_code):
> +        res += '\n\n\n'
> +        res += gen_wrapper(func)
> +
> +    return prettify(res)  # prettify to wrap long lines
> +
> +
> +if __name__ == '__main__':
> +    print(gen_wrappers_file(sys.stdin.read()))
> -- 

For Meson support, you'll have to move the "cat" inside the script.  But
since func_decl_iter can work separately on each file, it's enough to do
something like

    for filename in sys.argv:
        with open(filename, 'r') as f:
           print(gen_wrappers_file(f.read()))

Paolo



^ permalink raw reply	[flat|nested] 13+ messages in thread
end of thread, other threads:[~2020-08-20  7:39 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-10 10:03 [PATCH v7 0/7] coroutines: generate wrapper code Vladimir Sementsov-Ogievskiy
2020-06-10 10:03 ` [PATCH v7 1/7] block: return error-code from bdrv_invalidate_cache Vladimir Sementsov-Ogievskiy
2020-06-10 10:03 ` [PATCH v7 2/7] block/io: refactor coroutine wrappers Vladimir Sementsov-Ogievskiy
2020-06-10 10:03 ` [PATCH v7 3/7] block: declare some coroutine functions in block/coroutines.h Vladimir Sementsov-Ogievskiy
2020-06-10 10:03 ` [PATCH v7 4/7] scripts: add coroutine-wrapper.py Vladimir Sementsov-Ogievskiy
2020-08-20  7:38   ` Paolo Bonzini
2020-06-10 10:03 ` [PATCH v7 5/7] block: generate coroutine-wrapper code Vladimir Sementsov-Ogievskiy
2020-06-10 10:03 ` [PATCH v7 6/7] block: drop bdrv_prwv Vladimir Sementsov-Ogievskiy
2020-06-10 10:03 ` [PATCH v7 7/7] block/io: refactor save/load vmstate Vladimir Sementsov-Ogievskiy
2020-07-27 12:48 ` [PATCH v7 0/7] coroutines: generate wrapper code Stefan Hajnoczi
2020-07-27 12:59   ` Vladimir Sementsov-Ogievskiy
2020-08-20  1:33     ` Eric Blake
2020-08-20  7:34       ` Paolo Bonzini

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